Zinc Protoporphyrin IX in Meat and Meat Products: Formation, Application, and Future Perspectives.

Zinc protoporphyrin IX (ZnPP) is a naturally occurring metalloporphyrin that imparts a bright red color to nitrite-free dry-cured meat products such as Parma ham. This review explores the chemical structures, spectral characteristics, and mechanisms of ZnPP formation in meat products. ZnPP exhibits distinct absorption peaks in the Soret and Q bands, as well as a characteristic fluorescence emission peak at 590 nm. Its formation involves complex biochemical processes, including endogenous enzymatic, non-enzymatic, and bacterial enzymatic pathways. Various factors influence ZnPP formation, such as pH, muscle fiber type and meat composition, processing temperature and time, oxygen levels, and the presence of nitrites. ZnPP offers significant advantages for nitrite-free meat products by providing a stable red color without the associated health risks of N-nitrosamines. Furthermore, it aligns with consumer demand for clean-label products and benefits from advanced technologies that improve its scalability and industrial application. However, challenges persist in standardizing ZnPP production across diverse muscle types and optimizing its formation mechanisms. Future research should focus on developing innovative technologies to enhance ZnPP formation, exploring emerging markets for natural meat colorants, and further elucidating their mechanisms of action and potential health benefits. ZnPP is a promising natural alternative to synthetic nitrites in the meat industry and has the potential to revolutionize meat product coloration.